Ultrasonic surgical instruments are finding increasingly widespread applications in surgical procedures by virtue of the unique performance characteristics of such instruments. Depending upon specific instrument configurations and operational parameters, ultrasonic surgical instruments can provide substantially simultaneous cutting of tissue and hemostasis by coagulation, desirably minimizing patient trauma. The cutting action is typically effected by an end-effector at the distal end of the instrument, with the end-effector transmitting ultrasonic energy to tissue brought into contact therewith. Ultrasonic instruments of this nature can be configured for open surgical use, or laparoscopic or endoscopic surgical procedures.
Ultrasonic surgical instruments have been developed that include a clamp mechanism to press tissue against the end-effector of the instrument in order to couple ultrasonic energy to the tissue of a patient. Such an arrangement (sometimes referred to as an ultrasonic transector) is disclosed in U.S. Pat. No. 5,322,055, hereby incorporated by reference. However, typical constructions have included a clamp mechanism mounted in a fixed orientation relative to the handle or hand piece of the instrument. As such, a surgeon has typically been required to physically rotate the entire instrument in order to change the rotational orientation of the clamping mechanism. This can detract from convenient use of the instrument. In addition, conventional ultrasonic devices usually only use a single blade surface to cut or coagulate tissue. Therefore, a surgeon may have to change instruments for different cutting and coagulation applications.